You run it in such a way that the paths are identical. For example, by using the -r option. $ mkdir foo $ echo foo > foo/bar $ cp -a foo foo2 $ summain -r f

You run it in such a way that the paths are identical. For example, by using the -r option. $ mkdir foo $ echo foo > foo/bar $ cp -a foo foo2 $ summain -r foo > foo.summain $ summain -r foo2 > foo2.summain $ diff foo*.summain